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ProthenaSTU:0PT +2.49%74 PS Ratio is 8.17 as of Jul. 19, 2026, which is 85% below its 10-year median of 55.58. GuruFocus rates STU:0PT with a GF Score™ of 74/100 and a GF Value™ of €12.79. The stock has 3 warning signs investors should review. Among 930 Biotechnology companies, Prothena ranks better than 54.95% on this metric.
The PS Ratio, or Price-to-Sales ratio, or Price/Sales, is a financial ratio used to compare a company's market price to its Revenue per Share. As of today, Prothena's share price is €7.57.
Prothena's Revenue per Share for the trailing twelve months (TTM) ended in Mar. 2026 was €0.93. Hence, Prothena's PS Ratio for today is 8.17.
Good Sign:
Prothena Corp PLC stock PS Ratio (=8.08) is close to 1-year low of 7.7.
The historical rank and industry rank for Prothena's PS Ratio or its related term are showing as below:
STU:0PT'
s PS Ratio Range Over the Past 10 Years
Min: 1.83 Med: 55.58 Max: 2318.64
Current: 8.08
During the past 13 years, Prothena's highest PS Ratio was 2318.64. The lowest was 1.83. And the median was 55.58.
STU:0PT's PS Ratio is ranked better than 54.95% of 930
companies
in the Biotechnology industry
Industry Median: 9.3
vs STU:0PT: 8.08
Prothena Corp PLC revenue per share has been in decline over the past 3 years.
During the past 12 months, the average Revenue per Share Growth Rate of Prothena was -57.30% per year.
During the past 3 years, the average Revenue per Share Growth Rate was -45.90% per year.
During the past 5 years, the average Revenue per Share Growth Rate was 31.80% per year.
During the past 10 years, the average Revenue per Share Growth Rate was 43.00% per year.
During the past 13 years, Prothena's highest 3-Year average Revenue per Share Growth Rate was 456.60% per year. The lowest was -69.40% per year. And the median was -15.30% per year.
Back to Basics: PS Ratio
Prothena (STU:0PT) PS Ratio Explanation
The PS Ratio is an excellent valuation indicator if you want to compare a stock with its historical valuation or with the stocks in the same industry. The PS Ratio works especially well when you want to compare the stock's current valuation with its historical valuation. The PS Ratio is a great valuation tool for evaluating cyclical businesses where the PE Ratio works poorly. It works the best when comparing the current valuation with the historical valuation because over time, a company's profit margin tends to revert to the mean.
When the PS Ratio is applied to the whole stock market, it can be used to evaluate the current market valuation and projected returns. In this case, the price is the total market cap of all stocks that are traded, and sales are the GDP of the country. This is how Warren Buffett estimates the broad market valuation and project future returns.
The PS Ratio does not tell you how cheap or expensive the stock is. It cannot be used to compare companies in different industries. It works better for companies within the same industry because these companies tend to have similar capital structures and profit margins. It works the best when comparing a company with itself in the past.
Prothena PS Ratio Related Terms
Prothena PS Ratio Historical Data
* Premium members only.
The historical data trend for Prothena's PS Ratio can be seen below:
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
For the Biotechnology subindustry, Prothena's PS Ratio, along with its competitors' market caps and PS Ratio data, can be viewed below:
* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.
Prothena PS Ratio vs Biotechnology Industry
For the Biotechnology industry and Healthcare sector, Prothena's PS Ratio distribution charts can be found below:
* The bar in red indicates where Prothena's PS Ratio falls into.
The PS Ratio, or Price-to-Sales ratio, or Price/Sales, is a financial ratio used to compare a company's market price to its Revenue per Share. It is a ratio widely used to value stocks and it was first used by Ken Fisher.
Prothena's Share Price of today is €7.57. Prothena's Revenue per Share for the trailing twelve months (TTM) ended in Mar. 2026 adds up the quarterly data reported by the company within the most recent 12 months, which was €0.93.
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
It can also be calculated from the numbers for the whole company:
Prothena (STU:0PT) has a PS Ratio of 8.17 as of Jul. 19, 2026. Price-to-Sales ratio is the ratio of share price to a company's revenue per share. View historical data on Prothena and its competitors. This is 85% below median its historical median of 55.58. Over the past decade, Prothena's PS Ratio has ranged from 1.83 to 2,318.64. According to the industry distribution chart, Prothena ranks #419 out of 930 companies in the Biotechnology industry, placing it in the top 45.1%.
Is Prothena's PS Ratio too high?
Prothena's current PS Ratio of 8.17 is 85% below median its 10-year median of 55.58. Over the past 10 years, this metric has ranged from a low of 1.83 to a high of 2,318.64. The Biotechnology industry median PS Ratio is 9.30. Prothena's value of 8.17 is 12.2% below this industry median. Based on the distribution chart, Prothena ranks #419 out of 930 companies in the Biotechnology industry, which is above the industry midpoint. Overall, Prothena has a GF Score™ of 74/100, reflecting its overall financial health beyond just this single metric.
How does Prothena's PS Ratio compare to CTNM and ASMB?
According to the Biotechnology industry distribution chart, Prothena ranks #419 out of 930 companies for PS Ratio. This puts Prothena in the upper half of its industry. The industry median PS Ratio is 9.30. Prothena's value of 8.17 is 12.2% below this benchmark. Historically, Prothena's own PS Ratio has ranged from 1.83 to 2,318.64 over the past decade. While the company's 10-year median is 55.58 vs. the industry median of 9.30, Prothena has consistently been below the industry average. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good PS Ratio for a Biotechnology company?
The median PS Ratio among Biotechnology companies is 9.30, based on 930 companies in the industry. Companies in the top quartile (top 25%) have a PS Ratio significantly above this median, while those in the bottom quartile fall well below. However, PS Ratio should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Prothena's current PS Ratio of 8.17 is 12.2% below the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high PS Ratio mean?
A high PS Ratio can signal that a stock is expensive relative to its fundamentals. Price-to-Sales ratio is the ratio of share price to a company's revenue per share. View historical data on Prothena and its competitors. For the Biotechnology industry, the median PS Ratio is 9.30 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Prothena's current PS Ratio is 8.17, which is 85% below median its own 10-year median of 55.58. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Prothena stock overvalued right now?
Prothena (STU:0PT) has a current PS Ratio of 8.17. The stock's GF Value™ is €12.79, compared to a current price of €7.57 — trading 40.8% below its estimated fair value. The current PS Ratio is 8.17, which is 85% below median its 10-year median of 55.58 and 12.2% below the Biotechnology industry median of 9.30. Prothena's overall GF Score™ is 74/100 with 3 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is PS Ratio calculated?
PS Ratio is calculated from a company's financial statements. For Prothena (STU:0PT), the current PS Ratio is 8.17 as of Jul. 19, 2026. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.
Is Prothena (STU:0PT) Overvalued in 2026?
Based on GuruFocus' analysis, Prothena stock appears to be undervalued.
The current stock price of €7.57 is trading 40.8% below its estimated GF Value™ of €12.79.
Key valuation signals for STU:0PT:
PS Ratio: 8.17 (85% below median its 10-year median of 55.58)
GF Value™: €12.79 vs. price of €7.57 (40.8% below fair value)
Industry Position: 12.2% below the Biotechnology median (#419 of 930)
No single metric tells the full story. See the STU:0PT stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Prothena Corp PLC is a late-stage clinical biotechnology company that focuses on protein dysregulation and a pipeline of investigational therapeutics with the potential to change the course of devastating neurodegenerative and rare and peripheral amyloid diseases. Prothena is developing and applying its proprietary CYTOPE technology to target a broad spectrum of intracellular disease pathways in the brain and periphery. The company's pipeline includes both wholly-owned and partnered programs like Prasinezumab, Coramitug (PRX004), BMS-986446 (PRX005), PRX019, TDP-43 CYTOPE, and PRX012-TfR, being developed for the potential treatment of Parkinson's disease, ATTR amyloidosis with cardiomyopathy, Alzheimer's disease, Amyotrophic lateral sclerosis (ALS), and other neurodegenerative diseases.
74GF Score
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